Effects of environmental enrichment with classical music on the behavior of zebrafish subject to unpredictable chronic stress.
Classical music, homebase, UCS, zebrafish, stress, anxiety.
All living beings, regardless of their species or environment in which they are inserted, face stressful situations, predictable or not: food restriction, risk of predation, protection of offspring and other environmental conditions. As in many other species, exposure to something new can evoke anxiety responses in zebrafish, similar to what happens in rodents, for example, when placed in a new environment to observe their exploratory activity it presents a typical fear and anxiety behaviors in the species, such as freezing and reduced time at upper zone of the aquarium until the individual assesses whether it is safe to explore the environment. It is already known which exposure to chronic stress can contribute to development of anxiety and depression.
Many practices, mainly that use of controlled medication, have been used in order to minimize the negative effects of stress and psychiatric disorders. However, despite the benefits of using these drugs in therapeutic treatment, side effects deserve due attention, such as memory disorders, decreased psychomotor activity, mental confusion, social problems and abuse or dependence. It is known that prolonged consumption of anxiolytics can lead to tolerance, withdrawal and dependence. Based on that, some no-drugs alternative therapies are been adhered like auditory enrichment with classical music that improves welfare and reduces negative effects of stressful conditions. The auditory stimuli can affect physiology and behavior. It is already known that exposure to music, especially classical music, is beneficial in humans in reducing anxiety, improving sleep quality, reducing pain perception and is effective in environmental enrichment in several species. Therefore, music can be used as an alternative therapy in stressful situations. The zebrafish (Danio rerio) is a promising model to study human disorders in behavior, physiological responses and hearing research. To analyze the effects of classical music in stress, anxiety-like and depression-like behavior, we exposed adult zebrafish twice a day for 15 days of Vivaldi’s collection and tested in the open field, homebase formation and sociability test, to evaluate how UCS protocol (unpredictable chronic stress protocol) and music exposure can affect the exploration in the environment.